отрезок

#include <iostream>
#include <cmath>
#include <algorithm>

using namespace std;

struct otrezok
{
  double x1, y1, x2, y2;
  double len;
  //double *ostanovki;

  void length(double x1, double x2, double y1, double y2)
  {
    len = sqrt((x2-x1)*(x2-x1) + (y2-y1)*(y2-y1));
  };

};

int main ()
{
  otrezok bus_1;

  cin >> bus_1.x1 >> bus_1.y1;
  cin >> bus_1.x2 >> bus_1.y2;

  cout << bus_1.len << " ";

  bus_1.length(bus_1.x1, bus_1.x2, bus_1.y1, bus_1.y2);

  cout << bus_1.len;
}